Method for attaching a heat spreader to a semiconductor package and semiconductor package assemblies

Abstract

A method for attaching a heat spreader to a semiconductor package is provided. The method comprises: providing a semiconductor package, wherein the semiconductor package comprises a package substrate, a semiconductor component mounted on the package substrate and a mold cap formed on the package substrate and encapsulating the semiconductor component, and wherein the mold cap comprises a laser-activatable mold compound; removing a portion of a thickness of the mold cap above the semiconductor component by laser ablation to form a cavity in the mold cap and transform the laser-activatable mold compound at an inner surface of the cavity to a conductive layer; dispensing a thermal interface material (TIM) in the cavity to form on the conductive layer a TIM layer that protrudes from the mold cap; and attaching the heater spreader to the semiconductor package at least through the TIM layer.

1 . A method for attaching a heat spreader to a semiconductor package, the method comprising:
 providing a semiconductor package, wherein the semiconductor package comprises a package substrate, a semiconductor component mounted on the package substrate and a mold cap formed on the package substrate and encapsulating the semiconductor component, and wherein the mold cap comprises a laser-activatable mold compound;   removing a portion of a thickness of the mold cap above the semiconductor component by laser ablation to form a cavity in the mold cap and transform the laser-activatable mold compound at an inner surface of the cavity to a conductive layer;   dispensing a thermal interface material (TIM) in the cavity to form on the conductive layer a TIM layer that protrudes from the mold cap; and   attaching the heater spreader to the semiconductor package at least through the TIM layer.   
     
     
         2 . The method of  claim 1 , wherein the cavity in the mold cap extends across an entirety of the semiconductor component. 
     
     
         3 . The method of  claim 1 , wherein the semiconductor package is a strip type package, and wherein attaching the heater spreader to the semiconductor package at least through the TIM layer further comprises:
 dispensing an adhesive material on the mold cap; and   attaching the heater spreader onto the mold cap through the TIM layer and the adhesive material.   
     
     
         4 . The method of  claim 1 , wherein the semiconductor package is a unit type package, and wherein attaching the heater spreader to the semiconductor package at least through the TIM layer further comprises:
 dispensing an adhesive material on the package substrate; and   attaching the heater spreader onto the mold cap through the TIM layer and onto the package substrate through the adhesive material.   
     
     
         5 . The method of  claim 1 , wherein the laser-activatable mold compound comprises a base material and additives of metal particles that are openable by laser. 
     
     
         6 . A semiconductor package assembly, comprising:
 a semiconductor package, wherein the semiconductor package comprises:
 a package substrate, 
 a semiconductor component mounted on the package substrate, and 
 a mold cap formed on the package substrate and encapsulating the semiconductor component, wherein the mold cap comprises a laser-activatable mold compound, the mold cap comprises a cavity formed above the semiconductor component and having a conductive layer at its inter surface, and the cavity and the conductive layer are formed by laser ablation of the laser-activatable mold compound; 
   a thermal interface material (TIM) layer formed in the cavity of the mold cap and protruding from the mold cap; and   a heater spreader attached to the semiconductor package at least through the TIM layer.   
     
     
         7 . The semiconductor package assembly of  claim 6 , wherein the cavity in the mold cap extends across an entirety of the semiconductor component. 
     
     
         8 . The semiconductor package assembly of  claim 6 , wherein the cavity is formed such that a portion of a thickness of the mold cap remains above the semiconductor component and the TIM layer is not in direct contact with the semiconductor component. 
     
     
         9 . The semiconductor package assembly of  claim 6 , wherein the semiconductor package is a strip type package, and the semiconductor package further comprises an adhesive material on the mold cap through which the heat spreader is attached to the semiconductor package. 
     
     
         10 . The semiconductor package assembly of  claim 6 , wherein the semiconductor package is a unit type package, and the semiconductor package further comprises an adhesive material on the package substrate through which the heat spreader is attached to the semiconductor package. 
     
     
         11 . The semiconductor package assembly of  claim 6 , wherein the laser-activatable mold compound comprises a base material and additives of metal particles that are openable by laser.